Canon AC lenses for the T80 can now be used on some digital cameras
In the mid-1980s Canon made its first auto focus SLR camera (the T80), with a modified version of the FD manual focus lens mount, adding electrical contacts for a series of AC lenses with built in AF motors. The system was quickly abandoned after the introduction of the far superior EOS system of cameras and lenses shortly thereafter. Although the AC lenses don't fit EOS cameras, adapters are available for some digital compact system cameras.

Three Canon AC lenses were made – a 50mm f/1.8 standard prime, 35-70mm f/3.5-4.5 standard zoom and 75-200mm f/4.5 telephoto zoom – which seem to be based on the similar FD manual focus versions. The bayonet mount is the same as the manual focus FDn lenses, with the addition of extra electrical connections for the camera to power and control the AF motor, which was housed in a hump on the side of the lens.

Other digital cameras with adapters
As AC lenses use the FD bayonet mount, they can be fitted to some other cameras using suitable adapters. The lenses have no aperture rings, so an adapter with a diaphragm control is required (usually a ring marked something like Open<->Close or Open<->Lock). Adapters with no diaphragm control will only work at full aperture, and those with a fixed lever will only work at minimum aperture (effectively unusable). Also, the adapter must have a hole in the front of the lens mount for the AE Switch Pin, which is permanently engaged on AC lenses - without this, the lens won't fit. In fact, our experiments have shown that even some adapters with this hole don't seem to fit.

Adapters are (or have been) be available for use on digital compact system cameras including Canon EOS M, Fujifilm X, Leica T, M and SL, Olympus Pen and OM-D, Panasonic Lumix G, GH, GF, GM and GX Micro Four Thirds, Pentax Q, Samsung NX, Sony NEX, E-Mount and QX1, plus Ricoh GXR Mount A12, with manual focusing to infinity via the EVF or LCD, using manual diaphragm operation. Most cameras work in manual and aperture priority auto exposure modes only (no metering on some Nikon SLRs, metering restrictions on many Sony DSLRs). Full frame coverage on the Leica SL, Sony A7 and A9 cameras. Adapters may be available for use on the Nikon 1 series, with fully manual operation only (no metering). FD adapters are available for Canon EOS film and digital SLR cameras, but these require optical elements to retain infinity focusing, and the ones we've tried therefore don't fit AC lenses.

Please check below for a Products section with any suitable adapters we have in stock.